The present invention relates to a device for preparing a liquid, in particular, a device using a capsule containing one or more food ingredients for the preparation of a liquid. The invention also relates to a liquid dispenser using such a device. The present invention also relates to a capsule-holder of such a device using a capsule containing one or more food ingredients for the preparation of a liquid.
The use of capsules containing a substance for preparing a cold or hot drink by extraction or mixing with a pressurized fluid inserted into the capsule, such as water, is known particularly for producing a coffee of the espresso type, filter coffee, cappuccino, latte, macchiato, tea or chocolate, and is of value, in particular, for reasons of hygiene, freshness, conservation of the ingredients and ease of use.
Different types of machines are used for preparing drinks from sealed or permeable capsules containing a substance to be extracted such as ground coffee or tea, or a substance to be dissolved or dispersed such as instant coffee, chocolate or milk or a mixture or a simple combination of these substances. In general, the fluid for the extraction or dissolving of the substance is injected into the capsule through a wall; the extract or mixture is then formed in the enclosure of the capsule and it then pours in the form of a drink through one or more orifices. The injection may be carried out by an injector which pierces a membrane of the capsule or which inserts itself into a preformed inlet orifice of a wall of the capsule. The drink pours out of the capsule when a certain pressure is reached in the enclosure of the capsule. The capsule may thus interact with means used to delay the pouring, either opening means which open a wall of the capsule, for example reliefs against an outlet membrane, or else a filtering wall situated between the enclosure and the pouring orifice.
International Patent Application WO 03/059778 relates to a capsule containing one or more ingredients which are opened by opening means engaging with means of holding back the drink under the effect of the pressure rise in the capsule. Such a capsule has amongst other advantages: i) the possibility of distributing drinks of different natures “without cross-contamination”, that is to say without a first distributed drink transmitting one or more undesired characteristics, such as a taste, colour and/or odour, to a second drink distributed after the first, ii) the flexibility of designing capsules better suited to the ingredients and products to be distributed, iii) a better control and repetitivity of the extraction or mixing conditions, iv) a significant simplification of the distribution machine.
One disadvantage of the known systems of preparing drinks from a capsule arises from the fact that they are not usually designed to receive capsules of different shapes, sizes and/or requiring particular adaptations linked, for example, to the method of injecting the fluid into the capsule.
For example, a capsule containing a cappuccino mixture to be dissolved requires a larger volume, because the powdered milk that it contains takes up much more room than a capsule containing ground coffee for an espresso coffee, or else an instant coffee for a filter coffee. On the other hand, an instant coffee or tea usually requires less storage space. Also, certain soluble products, although not necessarily occupying a large volume, must nevertheless be dissolved in a gas-containing chamber of sufficient size in order to take on sufficient of this gas to create the froth. In order to reduce the packaging costs and take account of the characteristics or attributes of the drinks to be distributed (for example, a drink with froth or without froth), it is therefore preferable to design capsules whose size is suited to the ingredients contained and/or to the drinks prepared.
It is also known that the injection conditions considerably influence the quality of the drink produced. Depending on whether consideration is given to a substance originating from a grinding process or a substance to be dissolved or dispersed in a liquid such as instant coffee or a milk-based substance such as cappuccino, chocolate or other, or else a substance to be infused such as tea, the manner in which the water is delivered and circulates in the capsule may have a considerable influence on the quality of the final drink produced. The known devices are usually not designed to adapt or modify the conditions of injection according to the types of drinks to be produced.
Another disadvantage of the known devices arises from the fact that the injection means may rapidly become dirty and/or scaled and thus modify the characteristics of injection (like for example reducing the flow, increasing the pressure losses, modifying the direction of the jet, etc.) and therefore thus affect the quality and/or the attributes of the drink. These means are rarely accessible to the user. The user therefore has difficulty diagnosing the cause of the problem and consequently has difficulty remedying it.
European Patent Application EP 1 440 638 relates to a machine for the preparation of a drink using capsules; the machine comprising a first piercing element forming an inlet orifice and a second piercing element forming an outlet orifice; the orifices being formed during the use of the capsule; the two piercing elements being formed in a single removable unit. Such a configuration aims only to make the piercing elements easier to clean.
International Patent Application WO 2004/0006740 relates to a coffee machine operating with doses which comprise a support having two indentations placed side by side to receive two different doses. The indentations have annular bed-plates of different diameters, are offset in height, each corresponding to the dimensions of the flat bed-plate surface of a dose. In this case, only two different capsule volume options are available. Such a system is also relatively complex.
International Patent Application WO 97/43937 relates to an adaptator for prepacked coffee dose with a handle that defines a part of a percolating chamber suited to holding a dose of coffee; a lid associated to the dose-holder that defines a second part of the percolating chamber; the lid being suited to seal-lock with the lower part of a hot water distributor and bearing an aperture that connects the distributor to the percolating chamber. Such a principle aims at modifying the capsule-holder of a conventional hot water distributor but provides a number of disadvantages. First of all, the large fluid connection between the machine and capsule-holder poses a problem of hot residual water which can create safety issues as well as convenience problems. Secondly, the capsule holder is conceived to adapt to the water distributor via conventional closure means, such a bayonet type system, which involves a rotary mechanical tightening movement from the user. Such movement requires a certain strength of the user to be carried out and removal of the capsule holder might be difficult. Thirdly, the fluid connections of small size such as small fluid inlets for a providing high pressure water jets in the capsule-holder cannot be associated precisely and without risk of leakage. Therefore, this principle is only adapted for connecting to a large fluid outlet of boilers. Finally, the closure principle involves high torque that can affect the precision of the articulation of the lid and capsule holder. It may also affect the seal surfaces therefore providing rapid wear of the seal surfaces that needs to be compensated by more tightening.
European Patent Application EP 1 092 376 relates to an espresso coffee machine comprising a capsule-holder with handle containing the coffee powder, adapted to be operatively connected to the boiler portion of the coffee machine. This device presents the same disadvantages as the previous one.
Accordingly, there is a need for new devices that do not have such disadvantages, and these are now provided by the present invention.